Better markdown parse

[iamsolankiamit]

We need a handle parsing md and regenerating md from the parsed AST better, so the frontend/landr can better process the content.

• https://github.com/remarkjs/remark/tree/master/packages/remark-parse#readme
• https://github.com/remarkjs/remark/tree/master/packages/remark-stringify#readme
• https://github.com/remarkjs/remark-react